Trailer lighting testers – fast and reliable towbar wiring inspection
A correctly functioning towbar electrical installation is essential for safe driving with a trailer, bike carrier, tow dolly or caravan. Indicator lights, position lights, brake lights, rear fog lights and reversing lights must work properly not only during installation, but also in everyday vehicle use. This is why professional workshops are increasingly using trailer lighting testers, which allow them to quickly verify the correct operation of the module and the towbar wiring installation.
What is a trailer lighting tester used for?
A trailer lighting tester makes it possible to check the operation of the trailer lighting control module and verify whether the installation has been carried out correctly. The device allows the installer to confirm whether the module properly detects a connected trailer and whether individual lighting circuits operate as expected.
Quasar testers are designed for 13-pin trailer installations, and thanks to the use of an adapter, they can also be used with 7-pin installations. This means that one device can be used with different types of sockets commonly used in towbar wiring systems.
Testing the installation under load
One of the most important functions of the TMP02-G7G13 and TMP03-G7G13 testers is the simulation of loads generated by individual trailer light bulbs. This makes it possible to test the installation in conditions similar to real-life operation, rather than only checking whether voltage is present on the socket pins.
This solution helps verify whether the module correctly detects a connected trailer and properly handles individual lighting functions. It is particularly important in modern control modules, which respond to electrical load and may signal faults if the circuits do not operate correctly.
Which functions can be tested?
With our testers, you can check the most important functions of a trailer installation, including:
- indicator lights,
- position lights,
- brake light,
- rear fog light,
- reversing light,
- permanent +12 V supply,
- trailer battery charging voltage.
In addition, the testers allow the user to simulate a bulb failure and electrical trailer disconnection. This is very useful when checking whether the module responds correctly to faults and whether diagnostic functions operate as intended.
TMP02-G7G13 – wired trailer module tester
TMP02-G7G13 is a wired trailer module tester designed to check the correct operation and installation of a trailer lighting module. The device works with a 13-pin socket and, with the use of an adapter, also allows testing of 7-pin installations.
The tester is equipped with indicators showing the activation of individual trailer lights, as well as buttons that allow the user to simulate a failure of an indicator bulb, brake light or trailer disconnection. It also has a voltmeter that displays the current voltage value in the vehicle installation, making it possible to check, among other things, whether the trailer battery charging function has been activated correctly.
The set includes the tester with a 5-metre cable ending in a 13-pin plug, as well as a G7-G13 adapter. The long cable makes the device easy to use — it is long enough to operate the tester comfortably from the driver’s seat, without the need for an additional person.
TMP03-G7G13 – wireless trailer module tester
TMP03-G7G13 is a wireless trailer module tester designed for even more convenient testing of towbar wiring installations. The set consists of an actuator module connected to the trailer socket and a radio remote control operated from inside the vehicle cabin.
The actuator module simulates the loads of trailer light bulbs and transmits information about the signals present at the socket to the remote control. The remote is equipped with LED indicators, buttons for simulating faults and a voltmeter showing the current voltage in the vehicle installation.
Wireless communication makes one-person operation easier and eliminates the need for a long cable connecting the tester to the trailer socket. As a result, the TMP03-G7G13 is particularly well suited for workshops where speed, convenience and repeatability of the testing process are important.
TMP02 or TMP03 – which tester should you choose?
The choice of the right tester depends mainly on the way the workshop operates.
TMP02-G7G13 is a good choice for users who need a simple, robust wired tester for regular inspection of 7-pin and 13-pin installations. It is a practical solution for basic and effective verification of both the module and the towbar wiring installation.
TMP03-G7G13 is a more advanced option for workshops that want to improve the testing process. Thanks to radio communication, the person performing the test can operate the device from inside the vehicle cabin, without having to move between the trailer socket and the driver’s position. This solution increases working comfort and reduces the risk of damaging the tester cable.
Why is it worth using a trailer lighting tester?
A trailer lighting tester allows the installer to quickly detect possible installation errors, incorrect connections or problems with the module’s response to load. This gives the installer greater confidence that the towbar wiring installation is working correctly before handing the vehicle back to the customer.
Regular use of a tester also helps reduce diagnostic time, limit the number of complaints and avoid situations where a fault is detected only after a real trailer has been connected. This is especially important in professional workshops installing towbar wiring kits, where both quality of work and efficiency matter.
The TMP02-G7G13 and TMP03-G7G13 testers have been developed as practical tools supporting the installation and diagnostics of towbar electrical systems. They allow installers to check the most important trailer lighting functions, verify supply voltages and simulate faults, making it possible to quickly and effectively confirm the correct operation of the module.
These solutions are intended both for everyday workshop use and for quality control after installation. With them, trailer lighting testing becomes simpler, faster and more predictable.
